December 17, 2014
Benefits of Low-Dose Aspirin Outweighed by Risks in
Women up to 65

Utrecht, The Netherlands—The advantages of taking regular low-dose aspirin are outweighed by the disadvantages in women up to a certain age, but the balance shifts for women 65 and older.

That’s according to a study looking at the benefits versus risk for aspirin treatment to help prevent serious conditions such as cancer and heart disease. The results were published recently in the journal Heart.

The study, led by researchers from the University Medical Centre Utrecht in The Netherlands, found that limiting the regimen to the older cohort was more advantageous than either not taking aspirin at all, or treating women from the age of 45 onwards.

The research was based on the Women’s Health Study, focusing on nearly 30,000 healthy women who were at least 45 years old.

Participants were randomly assigned to take either 100 mg of aspirin or a placebo every other day to determine if aspirin reduced their risk of heart disease, stroke, and cancer.

During the 10-year trial period, the study group produced 604 cases of cardiovascular disease, 168 cases of bowel cancer, 1832 cases of other cancers, and 302 major gastrointestinal bleeds requiring hospitalization.

Over the next seven years, an additional 107 cases of bowel cancer and 1,388 other cancers were diagnosed.

Results indicate that the aspirin therapy, compared to placebo, had only a marginal link to reduced risk of heart disease, stroke, bowel cancer, and in some cases, other cancers.

Furthermore, the slight health improvement was overshadowed by the high prevalence of internal gastrointestinal bleeding, which affected two-thirds of the women taking the nonsteroidal anti-inflammatory drug.

“Although aspirin was associated with a modestly decreased 15-year risk of colorectal cancer, CVD, and in some women non-colorectal cancer, aspirin treatment resulted in a negative treatment effect in the majority of women if gastrointestinal bleeding was also taken into account,” the authors report.

Interestingly, both the risk of gastrointestinal bleeding and aspirin’s effect on lowering the risk of bowel cancer and cardiovascular disease increased with age, according to the results. The balance finally tipped in favor of the drug therapy when women reached 65 and older.

The authors calculated that over a 15-year period, 29 of the older women would need to be treated with aspirin to prevent one case of cancer or heart disease/stroke.

“Recent findings that both daily and alternate day aspirin can reduce cancer risk, particularly for colorectal cancer, have re-ignited the debate on aspirin in primary prevention,” the researchers write.

They conclude, however, that treatment without regard to age “is ineffective or harmful in the majority of women with regard to the combined risk of cardiovascular disease, cancer and major gastrointestinal bleeding,” but add, “Selective treatment of women ≥65 years with aspirin may improve net benefit.”

U.S. Pharmacist Social Connect